We investigated hypoxia-inducible factor (HIF)-dependent changes in the expression of 5592 genes in response to hypoxia ( O2, 16 h) by per-forming cDNA microarray analyses of mouse hepa1c1c7 and BpRc1 cells. BpRc1 cells are a hepa1c1c7 variant defective in HIF-b⁄aryl hydrocarbon receptor nuclear translocator (Arnt), and are therefore unable to induce HIF target genes in response to hypoxia.